Perceived Severity of Visually Accessible Fires

Investigations of past fires suggest that building occupants faced with a fire have problems defining the severity of it, especially in the early stages of the fire. An experiment was therefore carried out to study people’s ability to estimate fire growth, and their perceived ability to extinguish a fire using a portable fire extinguisher. A total of 535 persons, namely 304 men and 231 women, were asked to fill out a questionnaire that was divided into three parts. In the first part the test participants were asked to estimate the time between different stages of a fire. The second part involved estimations of the own ability to extinguish a fire with a portable fire extinguisher. The third part involved general questions about age, gender and academic background. The results suggest that people in general are not very good at defining the severity of a fire when it is visually accessible. Estimations of the fire growth did not correspond very well to the actual fire growth, and a great proportion of the test participants believed that they had not been able to extinguish an extinguishable fire using a portable fire extinguisher. It is therefore argued that the perceived risk not always conforms to the real risk in a fire situation where the fire is visually accessible. The results can be used to explain why building occupants not immediately initiate evacuation in a fire situation, even when the fire is visually accessible

Fire evacuation in underground transportation systems: a review of accidents and research

A review of literature related to fire evacuation in underground transportation systems, e.g., tunnels and subway stations, was carried out with the objectives (1) to identify a theoretical framework that can help understand of human behaviour in the event of a fire in underground transportation systems, (2) to use the theoretical framework to analyse and to identify problems related to fire evacuation in underground transportation systems, and (3) to suggest areas on which future research should focus on in. The review included literature on past accidents in underground transportation systems, theories and models on human behaviour in fire, and empirical research. It was concluded that the adoption of a clear theoretical framework can aid the understanding of people’s behaviour in the event of a fire in underground transportation systems, and that a behaviour that seems irrational to an outside observer seldom is. The theoretical framework should include the behaviour sequence model, the affiliative model, social influence, and the theory of affordances. It was also concluded that one of the major issues related to fire evacuation in underground transportation systems is that people often are reluctant to initiate evacuation, which among other things is explained with a role keeping behaviour, lack of information, ambiguity of fire cues and the presence of others, i.e., social influence. Other factors that affect the actual movement of people in underground transportation systems were identified as problems with the door-opening mechanisms on trains, the vertical distance between train and tunnel floor, that people tend to evacuate through familiar exits, the lack of lighting, and uneven surfaces inside tunnels. The review demonstrated that there are room for improvements in the area of fire evacuation in underground transportation systems, and future research should among other things study the effects of a comprehensive evacuation system, the optimal design of active systems in underground transportation systems, and the possibility for people with disabilities to evacuate from these types of facilities

Indoor Localization for Fire Safety : A brief overview of fundamentals, needs and requirements and applications

An indoor localization system for positioning evacuating people can be anticipated to increase the chances of a safe evacuation and effective rescue intervention in case of a tunnel fire. Such a system may utilize prevalent wireless technologies, e.g., Bluetooth, RFID and Wi-Fi, which today are used to survey incoming and outgoing traffic to a certain space or location, to estimate group sizes and to measure the duration of visits during normal operation of buildings. Examples also exist of where the same wireless technologies are used for safety purposes, for example to assess real-time location, tracking and monitoring of vehicles, personnel and equipment in mining environments. However, they are relatively few, and typically rely on a high degree of control over the people that are to be tracked, and their association with (connection to) the localization system used for the tracking. In this report, the results of a brief overview of the literature within the field of indoor localization in general, and the application of indoor localization systems within the field of particularly fire safety, is summarized. This information forms the underlying basis for the planning and execution of a future field study, in which an indoor Wi-Fi localization system will be tested and evaluated in terms of if, and if so how, it can be used to position evacuating people in tunnels. Whereas such a system allows digital footprints to be collected within a wireless network infrastructure (also already existing ones), questions remains to be answered regarding aspects such as precision and accuracy, and furthermore, how these aspects are affected by other independent variables. In the end of this report, examples of research questions deemed necessary to answer in order to enable a sound evaluation of the system is presented. These need to be addressed in the future planning of the above-mentioned field study

Delrapport: Test av vägledande system i en tunnel

I följande delrapport redogörs övergripande för förutsättningarna och delar av resultaten efter ett utrymningsförsök som genomfördes den 1-3 juli år 2014 i vägtunneln Norra länken i Stockholm. Syftet med försöket var i huvudsak att undersöka hur personer på bästa sätt kan ledas till en motstående tunnelvägg med utrymningsvägar i en rökfylld tunnel. Försöket syftade även till att kvantifiera med vilken hastighet människor rör sig i rökfyllda tunnelmiljöer (d v s vid nedsatta siktförhållanden). Baserat på en grov analys av de resultat som genererades under försöket kan det konstateras att designen av den utrymningsportal som användes under försöket till stor del verkar ha uppfyllt sitt ändamål (att få folk att använda nödutgångar i rökfyllda tunnelmiljöer). Det mest påtagliga resultatet är att det krävs någon form av vägledning för att personer som går längs den högra sidan ska förstå att de ska byta sida i höjd med utrymningsportalen. Åtminstone bör informationsskyltar installeras mittemot utrymningsvägarna för att upplysa utrymmande personer om att de befinner mittemot en utrymningsväg. Flera av försökspersonerna angav även att de utrymningsskyltar med information om avståndet till närmaste utrymningsväg var värdefulla. Det angav även flera av de personer som inte exponerades för denna typ av vägledande markeringar men istället som ett förslag för att få en bra utrymningsmiljö. För att ytterligare öka sannolikheten att människor vid en utrymning uppmärksammar och använder utrymningsvägarna föreslås att utrymningsportalerna även utrustas med aktiva högtalare. Flera av försökspersonerna som exponerades för denna installation uppgav att de hade nytta av den för att hitta utgången på den motsatta sidan

Test av vägledande system i en tunnel

The report outlines the conditions and results of an evacuation experiments performed on 1-3 July 2014 in the Northern Link road tunnel in Stockholm. The aim was mainly to investigate how people can best be led to an opposite tunnel side during escape in a smoke-filled tunnel. The experiment also aimed to quantify the speed at which people move in smoke-filled tunnel environments (i.e. at reduced visibility conditions). Based on the analysis of the results from the experiment it can be concluded that the design of the escape portal, which was used during the experiment, seems to have fulfilled its purpose (getting people to use the emergency exits in smoke-filled tunnel environments). The most obvious result is that some form of guidance is required to get people walking along the right hand side to understand that they should change side at the height of the escape portal. At a minimum, information signs should be installed opposite the escape route to inform escaping persons that they are standing opposite an escape route. Several of the subjects also indicated that the evacuation signs with information about the distance to the nearest escape route were valuable. This was also stated by several of the people who were not exposed to this type of signs but as a suggestion to get a good evacuation environment. To further increase the likelihood that people evacuating from the Stockholm Bypass it is suggested that evacuation portals also should be equipped with active speakers. Several of the subjects who were exposed to this installation indicated that they benefited from it in finding the exit on the opposite side

Positionering av människor i väg- och järnvägstunnlar i händelse av brand

The overall aim of the current project is to investigate the possibility of using people's mobile phones to locate people in a tunnel environment, both during normal operation and during an emergency. As part of the project, a technology for locating people based on Wi-Fi communication between access points in a tunnel and the user's mobile phone is investigated. To examine the precision of the localization system, 39 different trials have been carried out under various conditions during an experiment in a road tunnel in Stockholm, Sweden. In the tests, the Wi-Fi-based predicted location has been compared with the actual location, for each time step, of the people in the tunnel. The variables changed in the experiment include the number of people in a group, the number of available access points in the tunnel, whether the mobile phone distinguishes between an active or passive connection, whether it differs between a person moving or standing still, whether the mobile phone is held in the hand or is stored in the person's pocket and if there are obstacles in the tunnel (a vehicle). The results indicate that the mean value for the distance between actual and predicted position is in the order of 20 m or less. The variation in distance for a single individual is relatively large and the standard deviation for the mean distance is in the same order of magnitude as the mean value. Despite this, there is a good potential to locate individuals in a tunnel as the distance between emergency exits is often much longer than the uncertainties in the predicted locations of people. Also, the technology seems be able to predict the direction of movement for the individuals. These results are promising and indicates the potential of cost-efficient improvement of tunnel safety both for existing and new tunnels. With a refined positioning system, there is potential for further improved ability to locate individuals in a tunnel fire environment with this technology

Perceived Severity of Visually Accessible Fires

Investigations of past fires suggest that building occupants faced with a fire have problems defining the severity of it, especially in the early stages of the fire. An experiment was therefore carried out to study people’s ability to estimate fire growth, and their perceived ability to extinguish a fire using a portable fire extinguisher. A total of 535 persons, namely 304 men and 231 women, were asked to fill out a questionnaire that was divided into three parts. In the first part the test participants were asked to estimate the time between different stages of a fire. The second part involved estimations of the own ability to extinguish a fire with a portable fire extinguisher. The third part involved general questions about age, gender and academic background. The results suggest that people in general are not very good at defining the severity of a fire when it is visually accessible. Estimations of the fire growth did not correspond very well to the actual fire growth, and a great proportion of the test participants believed that they had not been able to extinguish an extinguishable fire using a portable fire extinguisher. It is therefore argued that the perceived risk not always conforms to the real risk in a fire situation where the fire is visually accessible. The results can be used to explain why building occupants not immediately initiate evacuation in a fire situation, even when the fire is visually accessible

Rail Tunnel Evacuation

In this thesis, human behavior in rail tunnel fires is explored. Descriptive knowledge is presented related to the evacuation of passenger trains, and the subsequent tunnel evacuation to a safe location. More specifically, a theoretical framework that can aid the understanding of human behavior is identified, and its applicability to rail tunnels is demonstrated. In addition, new empirical data on the flow rate capacity of train exits during evacuation in rail tunnels, as well as on walking speeds in smoke free and smoke filled rail tunnels, is presented. Finally, a number of technical installations that may facilitate orientation, movement and exit choice in rail tunnels are suggested. The findings are presented in relation to previously conducted empirical studies, and a discussion is also made on how the findings can be used in application and design

Evacuation of a Smoke Filled Tunnel: Human Behaviour, Movement Speed and Exit Choice

The report focuses on an evacuation experiment, which was performed within the second work package of the Swedish METRO project. The experiment involved 100 participants, both men and women in the ages 18-66 years, who individually evacuated a smoke-filled rail tunnel of approximately 200 metres length. The main purpose of the experiment was to collect and derive data on human behaviour and movement speeds, and to study the effectiveness of different technical emergency exit installations, systems and designs. In the report, an extensive description of the set-up, design and execution of the experiment is given. In addition, a thorough account of the analysis and outcome of the analysis is presented. Finally, a discussion is made and general recommendations and conclusions are presented